Reply To cazfi
Could it be explorer like in https://www.hostedredmine.com/issues/908297 ?
Ja, it could be. I was messing around with explorers a lot at that point, and, I did NOT know about this "'click and drag' toward a unit", until now, for any units. I think it's likely the same issue.
If this is https://www.hostedredmine.com/issues/908297 it doesn't need click and drag. All you need is to do is to ask for what actions are enabled against a tile where it is impossible to do anything and no good reason is found first. I'm not certain that it is https://www.hostedredmine.com/issues/908297 as the message you got catches a lot of crashes.
I saw these messages in the server console:
I didn't see when exactly it happened and I didn't notice any glitches in the game. Loading the savegame and repeating the actions does not repeat the messages.